Quantum Gravity, Flavour Vacua and Supersymmetry

I review a novel and non-perturbative way of breaking Supersymmetry in the flavour sector of electrically neutral particles, as a result of flavour mixing in the presence of stringy quantum gravity space-time foam backgrounds that violate Lorentz and CPT symmetries. In these models, part of the mixing may itself be induced dynamically by the interactions of the flavoured particles with the space-time foam.